A printer driver installed in a general PC (personal computer) generates a print stream if it is requested. This printer driver also has a function of canceling print processing. Japanese Patent Laid-Open No. 2000-253241 describes that upon sending print data from a personal computer (PC) to a printer via a printer driver on the PC, the print data of the printer driver of the PC is monitored to monitor copy inhibition information. In the description of this reference, the monitored print data (e.g., PDL data) is interpreted to check if it includes a specific character string or image. If it is determined that the specific character string or image is included, a print data transfer stop command is sent to the printer driver.
Conventionally, whether or not print processing is to be executed is determined to see if a connection path between the PC and printing apparatus is assured based on a use limitation. Hence, if a condition in which the PC makes the printing apparatus execute the print processing is met, data which is compatible with the printer driver can be printed. In this case, even data which is not preferably printed or should not be printed in a public place due to high security is printed if it is transmitted to the printing apparatus, thus posing a problem in terms of security of a highly confidential document.
In the example of Japanese Patent Laid-Open No. 2000-253241, print data of the printer driver is monitored parallel to generation and transfer of the print data by the printer driver so as to check if a copy inhibition image is included. Hence, depending on the check timing, the transfer inhibition command may be issued after transfer of print data from the printer driver is completed.